Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “PETROLOGY”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Petrology of Anomalous Mafic Achondrite Polymict Breccia Pasamonte

The most common asteroidal igneous meteorites are eucrite-type basalts and gabbros - rocks composed of ferroan pigeonite and augite, calcic plagioclase, silica, ilmenite, troilite, Ca-phosphate, chromite and Fe-metal [1]. These rocks are thought to have formed on a single asteroid, widely considered to be 4 Vesta, along with howardites and diogenites [1, 2]. High precision O-isotopic analyses have shown that some eucrites have small, well-resolved O-isotopic differences from the group mean [3-5]. These Oanomalous eucrites are thought to hail from asteroidal parents that are distinct from that of eucrites [5]. Three O-anomalous eucrites are PCA 82502, PCA 91007 (paired) and Pasamonte, all of which have the same O-isotopic composition [5, 6]. Our petrologic studies have shown that PCA 82502 and PCA 91007 have well-resolved anomalies in low-Ca pyroxene Fe/Mn compared to eucrites [6]. Divalent Mn and Fe are homologous species that do not greatly fractionate during igneous processes; mafic mineral Fe/Mn can be used to fingerprint parent object sources [7]. Previous petrological studies of Pasamonte [8-10] have not yielded sufficiently precise Fe/Mn ratios to allow distinction of anomalies of the scale of those found for the PCA basalts. We have begun petrological study of Pasamonte for comparison with our results on normal and anomalous eucrites [6], and to constrain its origin.

Mittlefehldt, D. W.↗
DOE OSTI2013

PETROLOGIC CONSTRAINTS ON AMORPHOUS AND CRYSTALLINE MAGNESIUM SILICATES: DUST FORMATION AND EVOLUTION IN SELECTED HERBIG Ae/Be SYSTEMS

The Infrared Space Observatory, Spitzer Space Telescope, and Herschel Space Observatory surveys provided a wealth of data on the Mg-silicate minerals (forsterite, enstatite), silica, and ''amorphous silicates with olivine and pyroxene stoichiometry'' around Herbig Ae/Be stars. These incredible findings do not resonate with the mainstream Earth Sciences because of (1) disconnecting ''astronomical nomenclature'' and the long existing mineralogical and petrologic terminology of minerals and amorphous materials, and (2) the fact that Earth scientists (formerly geologists) are bound by the ''Principle of Actualism'' that was put forward by James Hutton (1726-1797). This principle takes a process-oriented approach to understanding mineral and rock formation and evolution. This paper will (1) review and summarize the results of laboratory-based vapor phase condensation and thermal annealing experiments, (2) present the pathways of magnesiosilica condensates to Mg-silicate mineral (forsterite, enstatite) formation and processing, and (3) present mineralogical and petrologic implications of the properties and compositions of the infrared-observed crystalline and amorphous dust for the state of circumstellar disk evolution. That is, the IR-observation of smectite layer silicates in HD142527 suggests the break-up of asteroid-like parent bodies that had experienced aqueous alteration. We discuss the persistence of amorphous dust around some young stars and an ultrafast amorphous to crystalline dust transition in HD 163296 that leads to forsterite grains with numerous silica inclusions. These dust evolution processes to form forsterite, enstatite {+-} tridymite could occur due to amorphous magnesiosilica dust precursors with a serpentine- or smectite-dehydroxylate composition.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2014

Origin of the lunar highlands Mg-suite: An integrated petrology, geochemistry, chronology, and remote sensing perspective

The Mg-suite represents an enigmatic episode of lunar highlands magmatism that presumably represents the first stage of crustal building following primordial differentiation. This review examines the mineralogy, geochemistry, petrology, chronology, and the planetary-scale distribution of this suite of highlands plutonic rocks, presents models for their origin, examines petrogenetic relationships to other highlands rocks, and explores the link between this style of magmatism and early stages of lunar differentiation. Of the models considered for the origin of the parent magmas for the Mg-suite, the data best fit a process in which hot (solidus temperature at ≥2 GPa = 1600 to 1800 °C) and less dense (r ~3100 kg/m3) early lunar magma ocean cumulates rise to the base of the crust during cumulate pile overturn. Some decompressional melting would occur, but placing a hot cumulate horizon adjacent to the plagioclase-rich primordial crust and KREEP-rich lithologies (at temperatures of <1300 °C) would result in the hybridization of these divergent primordial lithologies, producing Mg-suite parent magmas. As urKREEP (primeval KREEP) is not the “petrologic driver” of this style of magmatism, outside of the Procellarum KREEP Terrane (PKT), Mg-suite magmas are not required to have a KREEP signature. Evaluation of the chronology of this episode of highlands evolution indicates that Mg-suite magmatism was initiated soon after primordial differentiation (<10 m.y.). Alternatively, the thermal event associated with the mantle overturn may have disrupted the chronometers utilized to date the primordial crust. Petrogenetic relationships between the Mg-suite and other highlands suites (e.g., alkali-suite and magnesian anorthositic granulites) are consistent with both fractional crystallization processes and melting of distinctly different hybrid sources.

58 GEOSCIENCES↗
DOE OSTI2013

Training Students to Analyze Spatial and Temporal Heterogeneities in Reservoir and Seal Petrology, Mineralogy, and Geochemistry: Implications for CO{sub 2} Sequestration Prediction, Simulation, and Monitoring

The objective of this project was to expose and train multiple students in geological tools that are essential to reservoir characterization and geologic sequestration including but not limited to advanced petrological methods, mineralogical methods, and geochemical methods; core analysis, and geophysical well-log interpretation. These efforts have included training of multiple students through geologically based curriculum and research using advanced petrological, mineralogical, and geochemical methods. In whole, over the last 3+ years, this award has supported 5,828 hours of student research, supporting the work of several graduate and undergraduate students. They have all received training directly related to ongoing CO{sub 2} sequestration demonstrations. The students have all conducted original scientific research on topics related to understanding the importance of lithological, textural, and compositional variability in formations that are being targeted as CO{sub 2} sequestration reservoirs and seals. This research was linked to the Mount Simon Sandstone reservoir and overlying Eau Claire Formation seal in the Illinois Basin- a system where over one million tons of CO{sub 2} are actively being injected with the first large-scale demonstration of anthropogenic CO{sub 2} storage in the U.S. Student projects focused specifically on 1) reservoir porosity characterization and evaluation, 2) petrographic, mineralogical, and geochemical evidence of fluid-related diagenesis in the caprock, 3) textural changes in reservoir samples exposed to experimental CO{sub 2} + brine conditions, 4) controls on spatial heterogeneity in composition and texture in both the reservoir and seal, 5) the implications of small-scale fractures within the reservoir, and 6) petrographic and stable isotope analyses of carbonates in the seal to understand the burial history of the system. The student-led research associated with this project provided real-time and hands-on experience with a relevant CO{sub 2} system, provided relevant information to the regional partnerships who are working within these formations, and provides more broadly applicable understanding and method development for other carbon capture and storage systems.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1971

Petrologic and mineralogic investigation of some crystalline rocks returned by the Apollo 14 mission.

Apollo 14 crystalline rocks (14053 and 14310) and crystalline rock fragments (14001,7,1; 14001,7,3; 14073; 14167,8,1 and 14321,191,X-1) on which Rb/Sr, Ar-40/Ar-39, or cosmic ray exposure ages have been determined by our colleagues were studied with the electron microprobe and the petrographic microscope. Rock samples 14053 and 14310 are mineralogically and petrologically distinct from each other. On the basis of mineralogic and petrologic characteristics all of the fragments, except 14001,7,1, are correlative with rock 14310. Sample 14073 is an orthopyroxene basalt with chemical and mineralogic affinities to ?KREEP,' the ?magic' and ?cryptic' components. Fragment 14001,7,1 is very similar to Luny Rock I.

Gancarz, A. J.↗
NASA NTRS1973

Constrained least-squares analysis of petrologic problems with an application to lunar sample 12040.

Many petrologic problems, which may be expressed as a set of linear equations, have been solved by least-squares analysis. In many cases insufficient attention has been paid to the physical conditions of the model resulting in incorrect application of the method. This paper presents a systematic treatment of the application of least-squares analysis to petrologic problems including the direct utilization of physical constraints and weighting factors in the problem, and the assessment of uncertainties in the solution. As an example, least-squares analysis is used to examine, in detail, the mass balance equations for lunar rock 12040 and to determine the consistency of the available analytical data.

Reid, M. J.↗
NASA NTRS1973

Lunar Science Conference, 4th, Houston, Tex., March 5-8, 1973, Proceedings. Volume 1 - Mineralogy and petrology. Volume 2 - Chemical and isotope analyses. Organic chemistry. Volume 3 - Physical properties

The mineralogy, petrology, chemistry, isotopic composition, and physical properties of lunar materials are described in papers detailing methods, results, and implications of research on samples returned from eight lunar landing sites: Apollo 11, 12, 14, 15, 16, 17, and Luna 16 and 20. The results of experiments conducted or set up on the lunar surface by the astronauts are also described along with observations taken from Command Modules and subsatellites. Major topics include general geology, soil and breccia studies, petrologic studies, mineralogic analyses, elemental compositions, radiometric age determinations, rare gas chemistry, radionuclides, organogenic compounds, particle track records, thermal properties, seismic studies, resonance studies, orbital mapping, lunar atmosphere, magnetic studies, electrical studies, optical properties, and microcratering. Individual items are announced in this issue.

Gose, W. A.↗
NASA NTRS1977

Mineralogy, petrology and chemistry of ANT-suite rocks from the lunar highlands

Anorthositic-noritic-troctolitic (ANT) rocks are the oldest and most abundant rocks of the lunar surface, and comprise about 90% of the suite of the lunar highlands. Consideration is given to the mineralogy, petrology, bulk chemistry, and origin of ANT-suite rocks. Problems associated in classifying and labeling lunar highland rocks because of textural complexities occurring from impact modifications are discussed. The mineralogy of ANT-suite rocks, dominated by plagioclase, olivine and pyrozene, and containing various minor minerals, is outlined. The petrology of ANT-suite rocks is reviewed along with the major element bulk composition of these rocks, noting that they are extremely depleted in K2O and P2O5. Various models describing the origin of ANT-suite rocks are summarized, and it is suggested that this origin involves a parental liquid of high-alumina basalt with low Fe/Fe+Mg.

Prinz, M.↗
NASA NTRS1975

Lunar Science Conference, 6th, Houston, Tex., March 17-21, 1975, Proceedings. Volume 1 - Mineralogical and petrological studies. Conference sponsored by NASA and Lunar and Planetary Institute

This book represents a conference whose main topics include: petrological studies of lunar samples, studies of anorthositic rocks, studies of soils and breccias, lunar minerology, petrologic studies of lunar problems, and petrogenetic models of lunar evolution. Attention is given to samples obtained from the Apollo 16 and 17 missions.

Merrill, R. B.↗
NASA NTRS1979

Apollo 12 feldspathic basalts 12031, 12038 and 12072 - Petrology, comparison and interpretations

The paper presents the petrology of Apollo 12 feldspathic basalts. Modal and chemical data indicate that basalts 12072, 12038, and 12031 cannot be related to the other Apollo rock types; 12072 contains phenocrysts of olivine and pigeonite, 12038 is a multiply saturated equigranular basalt, and 12031 is a coarse-grained rock with granular to graphic intergrowths of pyroxene and plagioclase. The bulk compositions indicate that these basalts could not have been derived from the Apollo 12 olivine or ilmenite basalts by crystal-liquid fractionation, and their petrologic similarities suggest that they were produced in the same or similar source regions.

Beaty, D. W.↗
NASA NTRS1980

The geology and petrology of the Apollo 11 landing site

Geochemical and petrologic data indicate that the 73 Apollo 11 basalts thus far identified can be divided into five petrologic groups (A, B1, B2, B3, D) which must represent at least five separate igneous cooling units. These five igneous bodies range in age from 3.90 b.y. to 3.60 b.y. Photogeologic studies indicate that three mare units are present, and that the lunar module set down on the oldest of the three. The exposure age data suggest that the high-K flow is the surficial rock type at the landing area, and is, therefore, probably the oldest of the three mare units. By examining the size frequency distribution and the inferred cooling rates of the individual samples, it is possible to calculate the formation thicknesses within the 30-m-deep West Crater. This suggests that A = 9 m, B1 = 2 m (and may be an ejecta blanket), B2 is equal to or greater than 8 m, and B3 = 6 m.

Beaty, D. W.↗
NASA NTRS1980

The lunar regolith - Comparative petrology of the Apollo sites

A description is presented of the modal petrology of eight surface soils from the Apollo 11, 12, 14, 15, and 16 landing sites. One of the most striking features of the petrology of the considered soils is found to be the similarity in distribution of pyroxene composition between the soil and the local rock types. The considered investigation is concerned with certain difficulties with respect to an understanding of regolith evolution. Lunar soils contain material foreign to the local geology. The foreign material must have been transported over long distances. However, models of regolith formation on the moon indicate that lateral transport is inefficient. It is found in the investigation that the soil is predominantly of local derivation, that lateral homogenization is a minor process, that foreign material is present in the amounts indicated by bulk chemical mixing models, and that preferential transport of fine-grained material does not occur.

Labotka, T. C.↗
NASA NTRS1982

The lunar regolith - Comparative studies of the Apollo and Luna sites. Petrology of soils from Apollo 17, Luna 16, 20, and 24

A progress report is presented concerning an investigation involving a comprehensive chemical and petrologic study of surface soils from all nine lunar sampling sites. The soils selected for this study are part of the lunar highlands soils suite and represent the soils at each site that contain abundant highland-derived material. The current report takes into consideration, in addition to the eight soils discussed by Labotka et al. (1980) and by Laul and Papike (1980), three Apollo 17 soils (72501, 76501, and 78221), and three Luna soils (21000, L-16; 22001, L-20; and 24999, L-24). Attention is given to the modal petrology of the 1000-90 micrometer fraction of all 14 soils, and the modes and mineral and glass chemistries of the 90-20 and 20-10 micrometer fractions of the Apollo 17 and Luna soils. In an evaluation of the obtained results, it is found that except for rare, large-scale impacts, lateral mixing is an inefficient process. Comminution and vertical mixing appear to be the dominant process.

Simon, S. B.↗
NASA NTRS1984

Petrologic comparisons of Cayley and Descartes on the basis of Apollo 16 soils from stations 4 and 11

Petrologic aspects of the Cayley and Descartes formations are reviewed in the light of new data on Apollo 16 soils. Specific comparison of the modal abundances of lithic fragments in drive tube sample 64001/2 from the slopes of Stone Mountain (station 4) and in soil 67941 from the North Ray Crater rim (station 11) shows that melt rocks, especially poikilitic rocks, are more abundant at station 4 than at station 11; the reverse is true for fragmental breccias. Such lithologic differences suggest that stations 4 and 11 do not belong to the same geologic formation. Metamorphosed breccias are pervasive in both the formations and may represent a local component that has been reworked and diluted as fresh materials were added. Lithologic compositions inferred from the study of soil samples are different from lithologic compositions inferred from the study of rake samples or breccia clasts. This difference may be related to a mixing of material of different grain size distributions. The petrology of soils at the Apollo 16 site may not accurately reflect original material associated with either the Descartes or the Cayley formation because of extensive mixing with local material.

Basu, A.↗
NASA NTRS1985

Constraints on chondrule origin from petrology of isotopically characterized chondrules in the Allende meteorite

The petrologic and chemical properties of the ferromagnesian chondrules in the Allende carbonaceous chondrite were examined in terms of the isotopic composition and the correlations between isotopic patterns. Areas of thin sections were studied with a SEM and bulk chemical fractions of 12 constituents were quantified to calculate correlations with petrologic features. A possible correlation between (CaO + Al2O2)/MgO and oxygen isotopes imply the formation of oxygen isotopic compositions in the chondrules by exchanges between isotopically heavy nebular gases and O-16 enriched solids. Different rates of gaseous exchange occurred with the various types of chondrules. Factors which may have controlled the exchanges are discussed.

Mcsween, H. Y., Jr.↗
NASA NTRS1986

Petrology, chemistry, and origin of Apollo 15 regolith breccias

Variations in modal petrology, mineral compositions, and bulk compositions were determined for ten Apollo 15 regolith breccias for comparison with local soils and assessment of the intrasite petrologic variability of the Apollo 15 regolith. Based on the above criteria the breccias are of local origin and mimic the soils from the corresponding sampling stations, with the exception of station 2 breccia 15205. This sample formed from an anomalous regolith, and although not considered exotic to the site is not representative of the soil at the site. KREEP basalt and green glass components vary from trace amounts to dominant in the breccias, evidence that these materials entered the regolith prior to formation of the breccias. Breccias from the edge of Hadley Rille are modally richer in highland fragments than the soils, whereas at the base of Hadley Delta the reverse is true. This is explained by the loss of material into the Rille to be replaced by basalt-derived material, making the soils more basalt-rich. At the base of Hadley Delta highland material is accumulating and the soils are becoming more highland-rich. Over billions of years these processes have developed differences between the present day, evolving soils, and 'fossil' nonevolving soils represented by the regolith breccias. This shows that there has been little change in the geology and the morphology of the Apollo 15 site, probably since the eruption of mare basalts at the site (about 3.3 b.y.).

Simon, S. B.↗
NASA NTRS1987

Global petrologic variations on the moon - A ternary-diagram approach

An improved method for global petrologic mapping of the moon is presented, which uses a color-coded ternary diagram whose apexes are assigned the average Fe and Th/Ti ratio (normalized to chondrites) compositions of KREEP/Mg-suite rocks, mare basalts, and ferroan anorthosites. The composition of each pixel within these Apollo orbital gamma ray data bases is used to determine its position within the ternary diagram. The color corresponding to this ternary position is then placed on a classification map at that pixel's position within the orbital data bases. The resultant classification map shows spatial transitions among petrologic units, allows direct determination of the relative proportions of each end-member composition in a pixel, and provides more geologic information than can be obtained by using only the elemental data. The map units correspond remarkably well to previously delineated geologic provinces.

Davis, Philip A.↗
NASA NTRS1987

The lunar regolith - Chemistry and petrology of Luna 24 grain size fractions

Chemical data obtained by instrumental neutron activation analysis are reported for 30 elements in eight lunar soil size fractions from 370 to less than 2 microns, as well as petrology for five size fractions down to 40-10 microns in two Luna 24 soils. While the compositions of coarser fractions are similar to each other, they differ from the fractions smaller than 10 microns; these become increasingly feldspathic and enriched in large ion lithophile elements (LILE) with decreasing grain size. The high concentrations of the Ni, Au and Ir meteoritic indicator elements in these finer fractions are consistent with comminution by meteoritic impact. Size distributions, petrology and LILE patterns indicate that Luna 24 soils are less reworked than most lunar soils.

Laul, J. C.↗